[layouts] Use correct transform context for map grids

nyalldawson · nyalldawson · commit 6f364fdba57e · 2018-01-29T10:57:02.000+11:00
Fixes #17984
diff --git a/src/core/layout/qgslayoutitemmapgrid.cpp b/src/core/layout/qgslayoutitemmapgrid.cpp
@@ -2329,8 +2329,7 @@ int QgsLayoutItemMapGrid::crsGridParams( QgsRectangle &crsRect, QgsCoordinateTra
       crsRect = tr.transformBoundingBox( mapBoundingRect );
     }
 
-    inverseTransform.setSourceCrs( mCRS );
-    inverseTransform.setDestinationCrs( mMap->crs() );
+    inverseTransform = QgsCoordinateTransform( mCRS, mMap->crs(), mLayout->project() );
   }
   catch ( QgsCsException &cse )
   {

Original file line number	Diff line number	Diff line change
`@@ -2329,8 +2329,7 @@ int QgsLayoutItemMapGrid::crsGridParams( QgsRectangle &crsRect, QgsCoordinateTra`
`2329`	`2329`	`crsRect = tr.transformBoundingBox( mapBoundingRect );`
`2330`	`2330`	`}`
`2331`	`2331`
`2332`		`- inverseTransform.setSourceCrs( mCRS );`
`2333`		`- inverseTransform.setDestinationCrs( mMap->crs() );`
	`2332`	`+ inverseTransform = QgsCoordinateTransform( mCRS, mMap->crs(), mLayout->project() );`
`2334`	`2333`	`}`
`2335`	`2334`	`catch ( QgsCsException &cse )`
`2336`	`2335`	`{`